TW202240228A - Lens assembly - Google Patents

Abstract

A lens assembly includes: a first lens including a protrusion; and a second lens disposed adjacent to the first lens and including a recess configured to accommodate at least a portion of the protrusion. The protrusion is spaced apart from the recess in an optical axis direction.

Description

lens group

The following description is about a lens group.

Recently, various types of lenses have been developed for the purpose of improving resolution or applying high magnification. Examples of such lenses may include D-cut lenses or free-form lenses. Freeform lenses and D-cut lenses are non-axisymmetric and thus may have differences in performance depending on alignment position with other optical elements (eg, other lenses, light blocking members, etc.). For example, even when a free-form lens is aligned with an adjacent lens on the optical axis, if the two lenses are assembled in a state deviated in the circumferential direction with respect to the optical axis, the resolution of the optical system may deteriorate.

This summary is provided to introduce a selection of concepts in a simplified form that are further explained below in the detailed description. This Summary is not intended to identify key features or essential characteristics of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In one general aspect, a lens assembly includes: a first lens including a protrusion; and a second lens disposed adjacent to the first lens and including a recess configured to receive at least a portion of the protrusion. The protrusion is spaced apart from the depression in an optical axis direction.

The lens group may further include a lens barrel configured to align the first lens with respect to the second lens in a direction perpendicular to the optical axis. The protrusion and the recess may be configured to limit rotation of the first lens relative to the second lens about the optical axis.

The protrusion and the depression may be spaced apart from each other in a direction perpendicular to the optical axis.

The lens group may further include a spacer disposed between the first lens and the second lens.

The protrusion and the depression may be provided in respective portions facing the spacer in the optical axis direction.

The spacer may include a through portion configured to allow the protrusion to pass therethrough.

The first lens may include a first optical portion exhibiting optical performance, and a first flange surface surrounding an outer circumference of the first optical portion and contacting the spacer. The protrusion may extend from the first flange surface toward the second lens.

The second lens may include a second optical portion exhibiting optical performance, and a second flange surface surrounding an outer circumference of the second optical portion and contacting the spacer. The depression may comprise a sunken portion of the second flange surface.

A depth of the recess from the second flange surface may be greater than a length obtained by subtracting a thickness of the spacer from a height of the protrusion protruding from the first flange surface.

The first lens may be non-axisymmetric with respect to the optical axis.

The first lens may be a D-cut lens.

The lens group may further include: a lens barrel for accommodating the first lens and the second lens. The first lens includes a linear portion and an arc portion, and the lens barrel may be configured to surround at least part of the arc portion and expose the linear portion in a direction perpendicular to the optical axis.

The lens barrel may include an opening portion exposing the linear portion. The linear portion may extend in a first direction perpendicular to the optical axis. The opening portion may expose the linear portion in a second direction perpendicular to both the optical axis and the first direction.

The first lens may be a free-form lens.

In another general aspect, a lens assembly includes: a first lens; a second lens adjacent to the first lens; and an alignment structure aligning the first lens and the first lens in a circumferential direction relative to an optical axis. The second lens is aligned. The alignment structure may be configured to allow movement of the first lens relative to the second lens in a direction perpendicular to the optical axis.

The alignment structure may include a protrusion disposed on the first lens and a depression disposed in the second lens. An air gap may be provided between the protrusion and the depression.

In another general aspect, a lens group includes: a first lens disposed on an optical axis; one or more protrusions protruding from a surface of the first lens in a direction parallel to the optical axis; a second lens disposed on the optical axis; and one or more depressions disposed on the surface of the second lens opposite to the surface of the first lens in the direction parallel to the optical axis on the surface. The one or more protrusions respectively extend only partially into the one or more recesses in the direction parallel to the optical axis.

The one or more protrusions may be disposed on the flange of the first lens, and the one or more depressions may be disposed on the flange of the second lens.

The lens group may further include a spacer disposed between the first lens and the second lens in the direction parallel to the optical axis. The spacer may include one or more openings elongated in a direction perpendicular to the optical axis and configured to respectively receive the one or more protrusions.

Each of the one or more protrusions may be configured to be aligned with a delimited portion in either or both of a radial direction relative to the optical axis and a circumferential direction relative to the optical axis. The walls of respective ones of the one or more openings are spaced apart.

Other features and aspects will be apparent by reading the following detailed description, drawings and claims.

The features described herein may be implemented in different forms and are not to be construed as limited to the examples described herein. Rather, the examples described herein are provided only to illustrate some of the many possible ways of implementing the methods, apparatus and/or systems described herein that will be apparent after understanding the disclosure of this application.

Throughout the specification, when an element such as a layer, region or substrate is described as being "on", "connected to" or "coupled to" another element, When an element is used, the element may be directly "on" the other element, directly "connected to" or directly "coupled to" the other element, or there may be one or more other elements intervening therebetween. . Conversely, when an element is described as being "directly on", "directly connected to" or "directly coupled to" another element, then There may be no other intervening elements.

As used herein, the term "and/or (and/or)" includes any one of the associated listed items and any combination of any two or more; similarly, "at least one of (at least one of)" includes any one of the associated listed items and any combination of any two or more of them.

Although terms such as "first", "second" and "third" may be used herein to describe various components, components, regions, layers or sections, these components, Components, regions, layers or sections are not limited by these terms. Rather, these terms are only used to distinguish the various components, components, regions, layers or sections. Therefore, the first component, component, region, layer or section mentioned in the examples herein may also be referred to as the second component, component, region, layer or section without departing from the teaching content of the example. segment.

For ease of description, spatially relative terms such as "above", "upper", "below", "lower" and similar terms may be used herein to describe all aspects in the drawings. The relationship of one element to another element is shown. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "upper" relative to other elements would then be oriented "below" or "lower" relative to the other elements. Thus, the term "above" encompasses both an orientation above and below, depending on the spatial orientation of the device. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative terms used herein interpreted accordingly.

The terminology used herein is to illustrate various examples only, and not to limit the present disclosure. The articles "a, an" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The terms "comprises", "includes" and "has" indicate the presence of stated features, numbers, operations, members, elements and/or combinations thereof, but do not exclude one or more other Existence or addition of features, numbers, operations, members, elements and/or combinations thereof.

As will be apparent after understanding the present disclosure, the features of the examples described herein can be combined in various ways. Furthermore, while the examples described herein have various configurations, other configurations are possible, as will be apparent after understanding this disclosure.

It should be noted that the use of the term "may" herein with respect to an example (eg, with respect to what an example may include or implement) means that there is at least one example in which such feature is included or implemented, and not all examples are limited thereto.

FIG. 1 is a cross-sectional view of a lens group 10 according to an embodiment.

Referring to FIG. 1 , the lens group 10 may include a lens barrel 100 and a first lens 200 and a second lens 300 accommodated in the lens barrel 100 . In the illustrated embodiment, only two lenses 200 and 300 are shown inside the lens barrel 100 , but this configuration is for ease of illustration only. In addition to the first lens 200 and the second lens 300 , one or more additional lenses can also be disposed in the lens barrel 100 .

In an embodiment, the lens group 10 may include a spacer 400 disposed between the first lens 200 and the second lens 300 . The spacer 400 may include a hole 404 through which light passes.

The spacer 400 may be configured to separate the first lens 200 from the second lens 300 at a specified interval. That is, the first lens 200 and the second lens 300 may be spaced apart from each other at a predetermined interval by the spacer 400 . For example, the spacer 400 may be manufactured such that the distance between the first lens 200 and the second lens 300 has a prescribed value.

The spacer 400 may serve as a light blocking member that blocks a portion of light passing through the first lens 200 . In such a case, the spacer 400 may help prevent a flare phenomenon.

For convenience of description, the lens group 10 shown in FIG. 1 schematically depicts the components of the lens group 10 , and the embodiments of the disclosure herein are not limited thereto.

FIG. 2 illustrates exemplary shapes of the first lens 200 , the second lens 300 and the spacer 400 accommodated in the lens barrel 100 shown in FIG. 1 . FIG. 3 is an exploded view of FIG. 2 . FIG. 4 is a cross-sectional view taken along line I-I shown in FIG. 2 . FIG. 5 is a diagram of the protrusion 203 and the depression 303 in the direction parallel to the optical axis O in the embodiment.

In an embodiment, the first lens 200 and/or the second lens 300 may be non-axisymmetric with respect to the optical axis O. For example, as shown in FIG. 2, the first lens 200 and the second lens 300 may be D-cut lenses. The D-cut lens may have a shape in which an edge of a circular lens is cut in a straight line.

The side surface of the first lens 200 may include a linear portion 211 and an arc portion 212 . The linear portion 211 is a portion extending in a direction perpendicular to the optical axis O on the side surface. The arc portion 212 is a portion extending in the circumferential direction on the side surface based on the optical axis O. As shown in FIG. The linear portion 211 may include two linear portions extending parallel to each other. For example, the two linear portions of the linear portion 211 may be spaced apart from each other in the Y direction, and may extend parallel to each other in the X direction. The arc portion 212 may include two arc portions facing each other. For example, the two arcuate portions of the arcuate portion 212 may be spaced apart from each other in the X direction.

The side surface of the second lens 300 may include a linear portion 311 and an arc portion 312 . The linear portion 311 is a portion extending in a direction perpendicular to the optical axis O from the side. The arc portion 312 is a portion extending in the circumferential direction around the optical axis O from the side. The linear portion 311 may include two linear portions extending parallel to each other. For example, two linear portions of the linear portion 311 may be spaced apart from each other in the Y direction, and may extend parallel to each other in the X direction. The arc portion 312 may include two arc portions facing each other. For example, the two arcuate portions of the arcuate portion 312 may be spaced apart from each other in the X direction.

In the present disclosure, the shape of each of the D-cut lenses can be defined by a shorter axis length and a longer axis length. Referring to FIG. 2 , the direction in which the two linear portions face each other is the shorter axis direction, and the direction in which the two arcuate portions face each other is the longer axis direction. For example, the shorter axis length can refer to the width of the D-cut lens in the Y direction, and the longer axis length can refer to the width of the D-cut lens in the X direction. The shorter axis length may correspond to the distance between the linear portions 211/311 of the D-cut lens.

In an embodiment, the first lens 200 and the second lens 300 include structures for mutual alignment.

In an embodiment, the lens barrel 100 may be configured such that a lens axis of the first lens 200 matches a lens axis of the second lens 300 . That is, when the first lens 200 and the second lens 300 are accommodated in the lens barrel 100 , the two lenses 200 and 300 may be aligned with each other in a direction perpendicular to the optical axis O. Referring to FIG.

When the lens is axisymmetric, only the lens axis needs to be aligned with the optical axis O, and even if the lens is rotated around the optical axis O, there is no change in optical performance relative to adjacent lenses. However, when the lens is non-axisymmetric, the optical characteristics vary with the rotation of the lens, and thus a structure for preventing the rotation of the lens is required.

In an embodiment, the lens group 10 may include a structure for aligning the first lens 200 and the second lens 300 in a circumferential direction (relative to the optical axis O). For example, the lens group 10 may include a structure preventing rotation between the first lens 200 and the second lens 300 relative to the optical axis O. Referring to FIG. Referring to FIG. 3 , in an embodiment, the first lens 200 may include a protrusion 203 , and the second lens 300 may include a recess 303 accommodating the protrusion 203 .

When viewed in a direction parallel to the optical axis O, the protruding portion 203 and the recess 303 are disposed at positions deviated from the optical axis O. As shown in FIG. Therefore, when the first lens 200 is disposed on the second lens 300 , mutual rotation of the first lens 200 and the second lens 300 can be prevented or minimized. In the following, the rotation of the lens refers to the rotation relative to the optical axis O.

In an embodiment, the protruding portion 203 and the recess 303 can be disposed at positions that do not damage the optical performance of the lens. In an embodiment, the first lens 200 may include an optical portion 201 exhibiting optical performance and a first flange surface 202 surrounding the outer circumference of the optical portion 201 , and the protrusion 203 may be formed on the first flange surface 202 . For example, the protrusion 203 can extend from the first flange surface 202 toward the second lens 300 . For example, in the view shown in FIG. 3 , the first flange surface 202 may be formed on the lower surface of the first lens 200 .

In an embodiment, the second lens 300 may include an optical portion 301 exhibiting optical performance and a second flange surface 302 surrounding the outer circumference of the optical portion 301 , and the depression 303 may be formed on the second flange surface 302 . For example, the depression 303 may be a portion of the second flange surface 302 that is sunken relative to an adjacent portion of the second flange surface 302 . For example, in the view shown in FIG. 3 , the second flange surface 302 may be formed on the upper surface of the second lens 300 .

In an embodiment, the height h of the protruding portion 203 and the depth d of the recess 303 may be within a range of greater than 0.03 mm and less than or equal to 0.2 mm.

In an embodiment, a plurality of protrusions 203 and recesses 303 may be arranged in a circumferential direction with respect to the optical axis O. Referring to FIG. In the illustrated embodiment, the protrusions 203 and the recesses 303 are provided in four pairs, but this configuration is only an example, and the protrusions 203 and the recesses 303 may be provided in one to three pairs or five or more pairs.

In an embodiment, the lens group 10 may further include a spacer 400 disposed between the first lens 200 and the second lens 300 . Referring to FIGS. 3 and 4 , the spacer 400 is mounted on the second lens 300 , and the first lens 200 is mounted on the spacer 400 . For example, the first flange surface 202 of the first lens 200 is in contact with one surface (for example, the upper surface 401 ) of the spacer 400 , and the second flange surface 302 of the second lens 300 is in contact with the other surface of the spacer 400 . Surfaces (eg, lower surface 402 ) are in contact.

In an embodiment, the through portion 403 of the spacer 400 may be provided as a slot extending in one direction (eg, extending a greater amount). The groove may open in the one direction. In an embodiment, the penetrating portion 403 may have a groove shape extending in a longer axis direction (ie, X direction) of the first lens 200 . Referring to FIG. 3 , the penetrating portion 403 may have a groove shape extending from a point where the protrusion 203 is located to an outer circumferential surface of the spacer 400 in the X direction. The shape of the through portion 403 may have any shape as long as the through portion 403 can accommodate the protrusion 203 , and the present disclosure is not limited to the shape of the through portion 403 shown.

In an embodiment, the protrusion 203 and the recess 303 are located at a portion facing the spacer 400 in the optical axis direction. For example, the first flange surface 202 of the first lens 200 faces the upper surface 401 of the spacer 400 , and the protrusion 203 is located on the first flange surface 202 . The second flange surface 302 of the second lens 300 faces the lower surface 402 of the spacer 400 , and the depression 303 is located on the second flange surface 302 .

In an embodiment, the protrusion 203 and the recess 303 may be configured to be spaced apart from each other. For example, the protrusion 203 and the recess 303 are configured to be spaced apart from each other in a direction parallel to the optical axis O (ie, the Z direction). For example, there is an air gap g1 in the direction of the optical axis O between the top surface 204 of the protrusion 203 and the bottom surface 304 of the recess 303 . That is, no other structure exists in the space between the protruding portion 203 and the recess 303 in the optical axis direction. For example, the depth d by which the depression 303 sinks from the second flange surface 302 may be greater than the length obtained by subtracting the thickness t of the spacer 400 from the height h of the protrusion 203 protruding from the first flange surface 202 ( That is, d>h-t).

In an embodiment, the protrusions 203 and the recesses 303 may be configured to be spaced apart in a direction perpendicular to the optical axis O. Referring to FIG. Referring to FIG. 4 , for example, an air gap g2 in the longer axis direction (ie, X direction) of the first lens 200 may exist between the protrusion 203 and the recess 303 . In another embodiment, there may be an air gap in the direction of the shorter axis of the first lens 200 (ie, the Y direction) between the protrusion 203 and the recess 303 .

Referring to FIG. 5 , in an embodiment, there may be air gaps g4 and g5 in the radial direction r and/or the circumferential direction c relative to the optical axis O between the protrusion 203 and the recess 303 . Hereinafter, the radial direction r and the circumferential direction c refer to the radial direction based on the optical axis O and the circumferential direction based on the optical axis O, respectively.

In an embodiment in which the air gap g5 exists in the circumferential direction c, relative rotation between the first lens 200 and the second lens 300 may be tolerated to some extent. However, the allowable rotation angle can be set within a range in which the optical performance of the optical system does not deteriorate. In the present disclosure, the optical system includes at least a first lens 200 and a second lens 300 .

In another embodiment, relative to the optical axis O, there may be no air gap g5 in the circumferential direction c between the protrusion 203 and the recess 303 . That is, the protrusion 203 and the recess 303 may contact each other in the circumferential direction c based on the optical axis O. Referring to FIG. Without an air gap in the circumferential direction c, relative rotation between the first lens 200 and the second lens 300 may be strictly limited.

In the embodiment, there is an air gap g4 in the radial direction r between the outer circumferential surface 205 of the protrusion 203 and the wall surface 305 of the recess 303 . That is, there is no other structure in the space in the radial direction r between the protrusion 203 and the recess 303 .

Referring to FIG. 4 , in an embodiment, an air gap g3 may exist between the protrusion 203 and the spacer 400 in a direction perpendicular to the optical axis O. Referring to FIG.

In an embodiment, the air gaps g1 , g2 , g3 , g4 , and g5 among the protrusion 203 , the recess 303 , and the spacer 400 may be in a range greater than 0 mm and less than or equal to 0.1 mm.

Since the centers of the first lens 200, the second lens 300, and the spacer 400 are aligned by the lens barrel 100, the lens 200, the second lens 300, and the spacer do not have a structure that restricts relative movement in the radial direction. The air gaps g1 , g2 , g3 , g4 and g5 as shown in FIG. 4 or FIG. 5 can also be maintained between 400 .

In an embodiment, the lens group 10 may include an alignment structure for aligning the first lens 200 and the second lens 300 in a circumferential direction with respect to the optical axis O. Referring to FIG. In an embodiment, the alignment structure may be configured to allow relative movement of the first lens 200 and the second lens 300 in a direction perpendicular to the optical axis. When the first lens and the second lens are coupled with the protrusion 203 received in the recess 303, the first lens may be allowed to move relative to the second lens in a direction perpendicular to the optical axis.

For example, the alignment structure includes a protrusion 203 and a recess 303 . Since the protrusion 203 and the recess 303 are spaced apart from each other in the direction perpendicular to the optical axis O, relative movement between the first lens and the second lens is possible in the direction perpendicular to the optical axis if there is no lens barrel. .

In the illustrated embodiment, the protrusion 203 is formed in the first lens 200 and the depression 303 is formed in the second lens 300, but this is only an example. However, in another embodiment, the protrusion 203 may be disposed in the second lens 300 and the depression 303 may be disposed in the first lens 200 .

FIG. 6 shows another example of the protrusion 203a disposed in the first lens 200a. FIG. 7 shows another example of the recess 303a disposed in the second lens 300a. 8 to 10 are examples of spacers according to the embodiment.

Referring to FIG. 6, the protrusion 203a may have a semi-cylindrical shape. Referring to FIG. 7 , the depression 303 a may be provided in a form extending in the circumferential direction (eg, extending by a larger amount).

Referring to FIG. 8, in an embodiment, the penetrating portion 403a of the spacer 400a may have the form of a groove extending in one direction. The groove may open in the one direction. For example, the penetrating portion 403a may be formed as a groove extending from the point P where the protrusion 203a is located to the outer circumferential surface of the spacer 400a in the Y direction.

Referring to FIG. 9 , the penetrating portion 403b of the spacer 400b may have a form in which a portion of the spacer 400b is cut in an 'L' shape. For example, a space between two edges extending in directions perpendicular to each other at the point P where the protruding portion 203 is located may be defined as the through portion 403b. Referring to FIG. 10, in an embodiment, the spacer 400c may be provided in the form of a hole.

The shapes of the protrusions and recesses shown in the drawings of the disclosure herein are examples only, and the disclosure is not limited to the examples described herein. In another embodiment, the protrusion (eg, protrusion 203 ) and the recess (eg, recess 303 ) may have various other shapes. That is, any arrangement of protrusions and recesses 303 can be adopted as long as the arrangement prevents the relative rotation of the first lens 200 and the second lens 300, and the protrusions 203 and recesses 303 can take into account various factors such as ease of manufacture performance or ease of assembly) are available in a variety of shapes.

FIG. 11 is a perspective view of a lens group 10 according to the embodiment. Fig. 12 is a sectional view taken along line II-II' shown in Fig. 11 .

Referring to FIG. 11 , the lens barrel 100 is configured to surround at least a portion of the first lens 200 . The lens barrel 100 surrounds the arc portion 212 of the first lens 200 in the circumferential direction. The arc portion 212 is surrounded by the lens barrel 100 and is not exposed outside the lens barrel 100 .

For example, the lens barrel 100 may include a flat portion 110 and a cylindrical portion 120 . The plate portion 110 is disposed on both sides of the first lens 200 . For example, the flat plate portion 110 may include two flat plates spaced apart from the optical axis O in the +Y direction and the −Y direction and facing each other. The cylindrical portion 120 surrounds the arc portion 212 of the first lens 200 in the circumferential direction. The arc portion 212 is surrounded by the lens barrel 100 and is not exposed outside the lens barrel 100 .

In an embodiment, the linear portion 211 of the first lens 200 may be exposed outside the lens barrel 100 . That is, the lens barrel 100 is configured not to cover the linear portion 211 of the first lens 200 . In an embodiment, the lens barrel 100 includes an opening portion 130 corresponding to the linear portion 211 of the first lens 200 , and the linear portion 211 may be exposed to the outside of the lens barrel 100 through the opening portion 130 . For example, when the linear portion 211 extends in the X direction perpendicular to the optical axis O, the linear portion 211 may be exposed in the Y direction through the opening portion 130 .

In an embodiment, the first lens 200 may extend to the opening part 130 . That is, the linear portion 211 of the first lens 200 may be located inside the opening portion 130 . For example, the lens barrel 100 may include an edge defining the opening portion 130, and the D-cut lens may extend to a space surrounded by the edge. That is, part or the whole of the linear portion 211 may be located in the space surrounded by the edge.

For example, referring to FIG. 12 , the distance between the linear portion 211 of the first lens 200 and the optical axis O may be greater than the distance between the optical axis O and the inner surface of the flat plate portion 110 . Although the related art lens barrel covers all sides of the D-cut lens, in an embodiment, the lens barrel 100 exposes at least part of the linear portion 211 of the first lens 200, which is the D-cut lens. In the case where there is no opening portion 130 in the flat portion 110 of the lens barrel 100 , the shorter axial length of the D-cut lens is limited by the interval between flat plates provided on both sides of the D-cut lens. On the contrary, according to an embodiment, since the opening part 130 is provided in the flat plate 110, the first lens 200 can be manufactured such that the shorter axis length (ie, 2*d1) is greater than the interval between the flat plate parts 110 (2*d3) .

According to an embodiment, the length of the D-shaped cut lens in the direction of the shorter axis can be longer than that of the related art, and an effective surface (ie, the optical portion 201 ) exhibiting optical performance in the D-shaped cut lens ) can be increased. This can help to improve the optical performance of the D-cut lens or the lens group 10 employing the D-cut lens.

When viewed from the perspective of the thickness of the lens barrel 100 , the effective surface of the D-cut lens can be increased without increasing the thickness of the lens barrel 100 . This may facilitate thinning of the lens group 10 or devices employing the lens group 10 . In addition, D-cut lenses are relatively easy to fabricate due to the reduced difference between the length of the minor axis and the length of the major axis. That is, the D-cut lens accommodated in the lens barrel 100 according to the embodiment may be manufactured relatively closer to a prescribed design.

In an embodiment, the lens barrel 100 surrounds only the arc portion 212 of the first lens 200 without a structure that suppresses the rotation of the first lens 200 in the rotation direction A. Referring to FIG. However, the lens barrel 100 may partially or entirely surround the side surface of the second lens 300 to limit the rotation of the second lens 300 . In addition, since the relative rotation of the first lens (for example, the first lens 200 ) and the second lens (for example, the second lens 300 ) is suppressed by the protrusion (for example, the protrusion 203 ) and the depression (for example, the depression 303 ) (or minimized), and thus rotation of the first lens 200 relative to the lens barrel 100 may be prevented or minimized even if the opening portion 130 exists.

FIG. 13 illustrates an alignment structure between adjacent first circular lenses 200-1 and second circular lenses 300-1 in an embodiment. The description of the protrusion 203 and the recess 303 is the same as that provided for FIGS. 1 to 10 , and will not be repeated hereafter.

In an embodiment, the first lens 200-1 may be non-axisymmetric with respect to the optical axis O, and may include an optical portion 201-1. The second lens 300-1 may include an optical portion 301-1.

In an embodiment, the first lens 200-1 may be a freeform lens. For example, the cross section of the first lens 200-1 including the optical axis O and taken in a plane parallel to the X-Z plane is the same as the first lens 200-1 including the optical axis O and taken in a plane parallel to the Y-Z plane. The cross-sections can have different shapes.

In an embodiment, the lens group may include a structure preventing rotation between the first lens 200-1 and the second lens 300-1 with respect to the optical axis O. Referring to FIG. In an embodiment, the first lens 200 - 1 may include a protrusion 203 , and the second lens 300 - 1 may include a recess 303 accommodating the protrusion 203 .

In an embodiment, the lens group may further include a spacer 400-1 disposed between the first lens 200-1 and the second lens 300-1. The spacer 400-1 is installed on the second lens 300-1, and the first lens 200-1 is installed on the spacer 400-1. For example, the first flange surface 202-1 of the first lens 200-1 is in contact with the upper surface 401-1 of the spacer 400-1, and the second flange surface 302-1 of the second lens 300-1 is in contact with the upper surface 401-1 of the spacer 400-1. The lower surface 402-1 of the spacer 400-1 is in contact.

As described above, the lens group according to the embodiment includes a structure for aligning the non-axisymmetric lens in the circumferential direction with respect to adjacent optical elements.

While this disclosure includes specific examples, it will be apparent upon understanding the disclosure of this application that forms and modifications may be made in these examples without departing from the spirit and scope of claims and equivalents thereof. Various changes in details. The examples set forth herein are intended to be considered as illustrative only and not for purposes of limitation. Descriptions of features or aspects within each example are intended to apply to similar features or aspects in the other examples. If the described techniques are performed in a different order, and/or if components of the described system, architecture, device, or circuit are combined in a different manner and/or are replaced or supplemented by other components or their equivalents, suitable results can be achieved. Therefore, the scope of the present disclosure is defined not by the detailed description but by the scope of patent claims and its equivalents, and all modifications within the scope of patent claims and their equivalents are intended to be construed as being included in the present disclosure.

10: Lens group 100: lens barrel/lens barrel 110: flat part 120: Cylindrical part 130: opening part 200: first lens/lens 200a: first lens 200-1: first lens/first circular lens 201, 201-1, 301, 301-1: Optical part 202, 202-1: first flange surface 203, 203a: protrusion 204: top surface 205: outer peripheral surface 211, 311: Linear part 212, 312: arc part 300: second lens/lens 300a: second lens 300-1: second lens/second circular lens 302, 302-1: second flange surface 303, 303a: depression 304: bottom surface 305: wall surface 400, 400-1, 400a, 400b, 400c: spacer 401, 401-1: upper surface 402, 402-1: lower surface 403, 403a, 403b: through part 404: hole A: Direction of rotation c: Circumferential direction d: depth g1, g2, g3, g4, g5: air gap h: height I-I', II-II': line O: optical axis P: point r: radial direction t: thickness X, Y, Z: direction

FIG. 1 is a cross-sectional view of a lens group according to an embodiment. FIG. 2 is a diagram illustrating two adjacent D-cut lenses in an embodiment. FIG. 3 is an exploded view of FIG. 2 . Fig. 4 is a sectional view taken along line I-I' shown in Fig. 2 . Fig. 5 is a diagram of protrusions and depressions in a direction parallel to the optical axis in the embodiment. Fig. 6 is another example of a protrusion provided in a lens. Fig. 7 is another example of a recess provided in a lens. 8 to 10 illustrate spacers according to embodiments. FIG. 11 is a perspective view of the lens group shown in FIG. 1 according to an embodiment. Fig. 12 is a sectional view taken along line II-II' shown in Fig. 11 . FIG. 13 illustrates the alignment structure between adjacent circular lenses in an embodiment. Throughout the drawings and detailed description, like drawing reference numbers will be understood to refer to like elements, features, and structures. The drawings may not be drawn to scale, and the relative size, proportion and presentation of elements in the drawings may be exaggerated for clarity, illustration and convenience.

10: Lens group

100: lens barrel/lens barrel

200: first lens/lens

300: second lens/lens

400: spacer

404: hole

O: optical axis

X, Y, Z: direction

Claims (20)

A lens group, comprising: a first lens including a protrusion; and a second lens disposed adjacent to the first lens and comprising a recess configured to receive at least a portion of the protrusion, Wherein the protrusion is spaced apart from the depression in the direction of the optical axis. The lens group according to claim 1, further comprising a lens barrel configured to align the first lens with respect to the second lens in a direction perpendicular to the optical axis, and Wherein the protrusion and the depression are configured to limit the rotation of the first lens relative to the second lens around the optical axis. The lens group according to claim 1, wherein the protrusion and the depression are spaced apart from each other in a direction perpendicular to the optical axis. The lens group according to claim 1, further comprising a spacer disposed between the first lens and the second lens. The lens group according to claim 4, wherein the protrusion and the depression are disposed in corresponding portions facing the spacer in the direction of the optical axis. The lens group according to claim 5, wherein the spacer includes a through portion configured to allow the protrusion to pass therethrough. The lens group according to claim 4, wherein the first lens includes a first optical portion exhibiting optical performance and a first flange surface surrounding an outer circumference of the first optical portion and contacting the spacer, and Wherein the protrusion extends from the first flange surface toward the second lens. The lens group of claim 7, wherein the second lens includes a second optical portion exhibiting optical performance and a second flange surface surrounding an outer circumference of the second optical portion and contacting the spacer, and Wherein said depression comprises a sunken portion of said second flange surface. The lens group according to claim 8, wherein the depth of the depression from the second flange surface is greater than that obtained by subtracting the spacer from the height of the projection from the first flange surface The length obtained from the thickness. The lens group according to claim 1, wherein the first lens is non-axisymmetric with respect to the optical axis. The lens set of claim 10, wherein the first lens is a D-cut lens. The lens group as described in claim item 11, further comprising: a lens barrel for accommodating the first lens and the second lens, Wherein the first lens includes a linear portion and an arc portion, and the lens barrel is configured to surround at least part of the arc portion and expose the linear portion in a direction perpendicular to the optical axis. The lens group according to claim 12, wherein the lens barrel includes an opening portion exposing the linear portion, the linear portion extends in a first direction perpendicular to the optical axis, and the opening portion The linear portion is exposed in a second direction perpendicular to both the optical axis and the first direction. The lens assembly of claim 10, wherein the first lens is a free-form lens. A lens group, comprising: first lens; a second lens adjacent to the first lens; and an alignment structure aligning the first lens with the second lens in a circumferential direction relative to the optical axis, Wherein the alignment structure is configured to allow the first lens to move relative to the second lens in a direction perpendicular to the optical axis. The lens group according to claim 15, wherein the alignment structure comprises a protrusion disposed on the first lens and a depression disposed in the second lens, and Wherein an air gap is provided between the protrusion and the depression. A lens group, comprising: The first lens is arranged on the optical axis; one or more protrusions protruding from the surface of the first lens in a direction parallel to the optical axis; a second lens disposed on the optical axis; and one or more depressions disposed on a surface of the second lens opposite to the surface of the first lens in the direction parallel to the optical axis, Wherein the one or more protrusions respectively only partially extend into the one or more depressions in the direction parallel to the optical axis. The lens group according to claim 17, wherein the one or more protrusions are disposed on the flange of the first lens, and the one or more depressions are disposed on the flange of the second lens . The lens group according to claim 17, further comprising a spacer disposed between the first lens and the second lens in the direction parallel to the optical axis, Wherein the spacer includes one or more openings elongated in a direction perpendicular to the optical axis and configured to respectively receive the one or more protrusions. The lens group according to claim 19, wherein each of the one or more protrusions is configured in a radial direction relative to the optical axis and a circumferential direction relative to the optical axis Either or both are spaced apart from a wall defining a respective one of the one or more openings.

Images